I'd like my customer to be able to edit the data that they input when signing up but the profile form is different. I don't understand the purpose of the profile form if it is not used to edit their sign up info. Thanks.
OK... I figured it out. The signup form and the profile form ARE basically the same but you have to add the same fields to both if you want the customer to be able to edit everything... or you can just add those fields that you want the customer to be able to edit.
Yes - you're right. Plus you can also use the 'configure' option on the form bricks in the Profile form to set some fields as 'read only', which is useful if you do not want your user to be able to edit some of the information that you hold.